1. Field of the Invention
The present invention relates to methods and apparatuses for generating and editing a three-dimensional (3D) model, and more particularly, to methods and apparatuses for generating and editing a 3D model, which can more precisely generate a 3D model and can more quickly edit the 3D model using depth information of the 3D model.
2. Description of the Related Art
Since the first research into 3D graphics, one of the most fundamental goals of 3D graphics has always been to generate 3D models more precisely and more quickly. Recent multimedia applications require user devices, such as mobile devices, to more quickly and more precisely generate 3D models in a network environment. However, a conventional mesh-based generating technique using a polygonal mesh has failed to meet this requirement satisfactorily. For example, in the case of generating a complicated 3D model on a small screen of a terminal device using the conventional mesh-based generating technique, some information on links between vertices may be redundant. Complex meshes must be simplified in order to enable interactive 3D model renderings. In order to simplify such complex meshes, however, complex algorithms are necessary. In addition, complex algorithms are also needed to compress meshes and transmit the compressed meshes progressively.
A conventional image-based rendering technique, which is an alternative to the conventional mesh-based rendering technique, can render image-based or point-based 3D models with high resolution by using images having depth information, i.e., depth images. The image-based rendering technique can also appropriately process or edit image data and can render 3D models in real time.
The conventional image-based rendering technique, however, renders the 3D model without considering the fact that reference images of the 3D model may include redundant data of the simple texture model that render the same portion of the 3D model from different viewpoints, thereby considerably degrading the rendering speed and quality.
In addition, the conventional image-based rendering technique cannot satisfactorily render various surface characteristics of a 3D model, such as glitter or shade varying from viewpoint to viewpoint. Therefore, a 3D model rendered by the conventional image-based rendering technique may not be realistic. Moreover, the conventional mesh-based rendering technique needs complex algorithms because it provides no other option but to modify every reference image of an image-based 3D model in order to modify the image-based 3D model, in which case, the amount of image data needed to be edited is considerable.